docstr: Graph Laplacian
docstr_tok: ["Graph","Laplacian"]
file_path: networkx/networkx/linalg/tests/test_laplacian.py
imports: import pytest
  import networkx
  from networkx.generators.degree_seq import havel_hakimi_graph
  from networkx.generators.expanders import margulis_gabber_galil_graph
label_desc: Use image node_id 2 for calling the TestLaplacian obj's underlying member method code with example usage: obj.test_laplacian() without return types